My first thought is have you changed how you loaded the rig meaning maybe less tongue weight then before which under certain conditions would allow the stinger to move slightly and make noise. I will get some movement (noise) from mine when driving in very curvy roads at highway speeds.
Jake my sidekick (yellow Lab) 10/04 - 05/20
2017 RAM 2500 CC 4X4 Cummins Diesel
2016 Flagstaff 26 FKWS
AF&AM & El Korah Shrine of Idaho